Recently, in accordance with an increase in carbon dioxide emission due to consumption of fossil fuel, a rapid change of crude oil price, and the like, development of a technology of converting from gasoline and diesel oil to an electric energy as an energy source of automobile has been spotlighted. Commercialization of an electric automobile has progressed, and for a long-distance driving, a lithium ion battery which is a storage battery has been required to have large capacity and high energy densification. However, the current lithium ion battery has a limitation in battery capacity, which has difficulty in a long distance driving. Therefore, research into a lithium air battery having larger capacity and higher energy density than those of a theoretical lithium ion battery has been actively conducted.
In general, the lithium air battery includes an anode capable of adsorbing and emitting lithium ions, a cathode including an oxidation-reduction catalyst using oxygen in the air as a cathode active material, wherein a lithium ion conductive medium is provided between the cathode and the anode. That is, the lithium air battery, which is a battery having the cathode using oxygen in the air as the active material, is a battery capable of charging and discharging the battery by performing an oxidation-reduction reaction of oxygen in the cathode.
The lithium air battery has a theoretical energy density of 3000 Wh/kg or more, which corresponds to an energy density about 10 times larger than that of the lithium ion battery. In addition, the lithium ion battery is environmentally friendly and provides improved stability as compared to the lithium ion battery.
However, an electrode structure of the existing lithium air battery has problems in that at the time of charging and discharging the battery, a large amount of an electrolyte contacts a catalyst layer to generate overvoltage, or a solvent of an electrolyte used between the solid electrolyte and a porous air-cathode is evaporated, such that the lithium air battery has deteriorated performance and reduced a lifespan.
As the related art document regarding the above-description, U.S. Patent Application Publication No. 2012/0028164 A1 entitled “lithium air battery” is disclosed.